provide hatari config with launcher

src/MarcerGameDvdLauncher/HatariLauncher.cs

@@ -5,6 +5,11 @@ namespace MarcerGameDvdLauncher
 {
     public class HatariLauncher
     {
+        // The Hatari configuration file that is shipped with the launcher.
+        // When Hatari.ConfigFile is not set in launcher.config.json, this file
+        // (resolved relative to the executable directory) is used automatically.
+        public const string DefaultConfigFile = "MarcerGameDvd-Hatari.cfg";
+
         private readonly string _exePath;
         private readonly string _cfgPath;
         private readonly string _argsTemplate;

src/MarcerGameDvdLauncher/LauncherApp.cs

@@ -63,8 +63,15 @@ namespace MarcerGameDvdLauncher
             if (!File.Exists(cfg.Hatari.Executable))
                 throw new InvalidOperationException($"Hatari executable not found: {cfg.Hatari.Executable}");
 
-            // Also validate the Hatari config file (if provided)
-            if (!string.IsNullOrWhiteSpace(cfg.Hatari.ConfigFile) && !File.Exists(cfg.Hatari.ConfigFile))
+            // If no Hatari config file was specified, fall back to the bundled
+            // MarcerGameDvd-Hatari.cfg that ships with the launcher.
+            if (string.IsNullOrWhiteSpace(cfg.Hatari.ConfigFile))
+            {
+                cfg.Hatari.ConfigFile = Path.Combine(exeDir, HatariLauncher.DefaultConfigFile);
+            }
+
+            // Validate the Hatari config file (either user-specified or bundled fallback)
+            if (!File.Exists(cfg.Hatari.ConfigFile))
                 throw new InvalidOperationException($"Hatari configuration file not found: {cfg.Hatari.ConfigFile}");
             if (string.IsNullOrWhiteSpace(cfg.Hatari.ArgsTemplate) || !cfg.Hatari.ArgsTemplate.Contains("{zip}"))
                 throw new InvalidOperationException("Hatari.ArgsTemplate must contain the {zip} placeholder.");

src/MarcerGameDvdLauncher/launcher.config.example.json

@@ -3,7 +3,7 @@
   "PatchDirectory": "C:\\Games\\Hatari\\PATCH",
   "Hatari": {
     "Executable": "C:\\Tools\\hatari\\hatari.exe",
-    "ConfigFile": "C:\\Tools\\hatari\\hatari-st.cfg",
+    "ConfigFile": "",
     "ArgsTemplate": "-c \"{cfg}\" --disk-a \"{zip}\""
   },
   "Colors": {